Wireless communications services have grown in popularity in recent years. The demand for services such as paging, cellular, personal communications services and mobile radio, has increased and customers expect high quality, low cost service. Many telecommunications providers are transitioning from the well-established analog cellular service to digital cellular service where more features and services are possible. For example, currently the majority of wireless traffic is voice traffic but in the near future the telecommunications companies predict that digital service demands will exceed requirements for voice service.
Cellular telephone networks typically involve numerous service providers and equipment. For instance, a local telephone company may manage the service from a cell site to a switch where a long distance provider switches the call throughout its network to call completion. Alternatively, one company can provide end to end service. Or a combination occurs where a local company takes the call from the cell site to locations within its local territory and to a long distance provider who switches the call across the country. Potentially, a multitude of service providers can be involved as voice and data communications traffic travels from end to end. As the number of providers increases, sources of potential problems grows requiring effective, efficient trouble isolation for problem resolution.
While the reliability of wireless communications networks has increased, often, cell sites stop working. Determining where the problems reside is challenging because communications networks include numerous components, such as, cell site equipment, central office equipment, and facilities, all which can be provided by different service providers.
One method for clearing troubles is to utilize a central network management center with remote access to certain portions of the network. The network management center checks a portion of the network. Either the network management center personnel clear the trouble remotely or they dispatch a technician to the troubled location to clear the problem. Technicians provide hands on support for both installation and maintenance of the communications network. The technician must drive to the cell site location, determine the problem and correct the problem. To determine what portion of the network is in trouble, the technician must eliminate a multitude of problems, for instance, a down telephone link to the cell site, broken cell site equipment, damage to the cell site caused by lightening, or conclude that the problem is somewhere else in the network. Cell sites can be geographically dispersed, perhaps remotely located, such as in a wooded area, requiring a technician to drive several hours just to reach the cell site. Thus, isolating a problem is a long arduous process.
In the current environment, historical performance data of the transport link to the cell site can be provided, however, real time information cannot be provided. Thus, a technician may arrive at the trouble location only to find that no trouble exists because, for instance, the trouble became clear in the time it took for the technician to arrive, the problem was not isolated to the correct piece of equipment, or the facility works properly from the technician's location towards the central office and the problem exists in a another portion of the network.
Solving these problems requires coordination among numerous people including: local carriers, long distance carriers, independent carriers, and equipment vendors. One call could involve as many as forty different carriers, making coordination between carriers a time consuming and challenging task. Customer satisfaction suffers when technicians or network management center personnel cannot correctly identify the problem or when the problem cannot be timely resolved due to coordination problems among the various suppliers. Customer satisfaction also suffers when the problem “came clear” since the customer may not be satisfied that the problem will not occur again. Solving problems is exacerbated when a cellular network contains thousands of cell sites, each of which could at some point have trouble requiring technician dispatch to resolve.
Several types of wireless communications services exist, such as the North American Global System for Mobile Communications (GSM) cellular communications networks, code division multiple access (CDMA) and time division multiple access (TDMA) networks. Each network typically includes a cell site having a tower and associated equipment, a customer service unit (CSU), transport links, central office equipment, and facilities connecting the transport link to a switch. Currently, central office or network management center personnel cannot remotely test the transport link in real time all the way to the cell site. Most failures in a cellular network occur between the transport links connecting the cell site to the switch, where real time remote testing is unavailable. Only historical (e.g., past) data on a circuit performance is available. Thus, no effective real time system or method exists for remote testing or performance monitoring of the transport links connecting cellular sites to a switch. Remote testing personnel and other maintenance personnel cannot “see” what is happening beyond channels in a digital access and cross connect system (DACS) in the central office. If the location where the trouble occurred cannot be identified, repairing the problem is more challenging. Thus, preventative testing or performance monitoring of any transport links must be performed by local field technicians utilizing performance reports with only historical data derived from an operations management center. The operations management center using the historical data produce historical transmission statistics that then can be reviewed manually to gain some insight into the health of the transport links. Resource and technological constraints currently prevent any effective proactive, real time circuit monitoring and maintenance.
As the cellular transport network becomes larger and more complex, insuring transport link quality becomes a greater challenge. Without the capability of robust remote testing, monitoring and analytical systems, the network is subject to less than optimal transport link quality, a greater number of field technicians are needed to handle transport link problems, and transport link maintenance suffers as a result of field technicians working priority outages.
Due to bandwidth limitations and limitations in the existing CSU, network performance monitoring has not reached the cell site. As a result, existing network monitoring configurations stop at the transport hub where some piece of edge transmission equipment resides.
Thus, this invention addresses the problems in the prior art and provides systems and methods for remote testing and performance monitoring of a cellular communications network that brings transmission surveillance to the cell site.